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DU Special Report
Prairies Under Siege: Part IV
The
Future of the Prairies
Without aggressive measures to secure its habitat base, North Americas
duck factory faces an uncertain future
By Jim
Ringelman, Ph.D.
Its tough to
wrap your mind around some things. Like the size of the national debt or the
number of humans inhabiting planet earth. I throw the Prairie Pothole Region
(PPR) into this same mix of imponderables. More than 300,000 square miles in
size, millions of wetlands, and tens of millions of breeding ducks. It seems
impossible that the hand of mankind could cause much change in such a vast
landscape. But we have. And were threatening to do more damage in the next
decade than in any time in recent history. What could be the effect on duck
populations and duck hunting? Intriguing new analyses provide a troubling
answer.
Recently, researchers compiled data from many sources to address the question
What causes the mid-continent mallard population to change? The answer
reaffirmed what many biologists have long suspected: Events that occur during
the breeding season account for 84 percent of the variability in the mallard
population growth rate (Figure 1). Surprisingly, deaths that occur during the
nonbreeding seasonincluding that from huntingaccounted for just 9 percent of
the change in the population growth rate. And because mallard population
ecology is similar to that of many other upland-nesting dabbling ducks, we now
believe that mid-continent populations of these other species are regulated by
the same set of factorsnesting success, hen success, and duckling and hen
survival during the breeding season. This finding has big implications for duck
hunters.
Of the top 10 harvested duck species, six of them achieve their highest nesting
densities in the PPR, and two more split their breeding range between the
prairies and forested habitats. Collectively, these eight species made up
nearly 80 percent of the U.S. harvest in 2002-2003. Clearly, if youre a duck
hunter, the chances are good that the PPR is supplying you with many, if not
most, of the birds on your duck strap. The science is unequivocal, and it all
points to the importance of the prairies. This is where Ducks Unlimited began
its work 67 years ago, and where DU is focusing its resources in its efforts to
save this imperiled ecosystem.
Keeping
the Table Set
To understand DUs philosophy about prairie conservation, one must first
recognize the most unique feature of the prairies: their dynamic environment.
Floods and drought. Extreme heat and bitter cold. Occasional fires and gusty
winds. The prairie ecosystem has not only evolved under these dynamic
conditions, it requires them to maintain its productivity. Waterfowl have
adapted to this variability by capitalizing on the fertility of reflooded
prairie wetlands when good times prevail, and abandoning the region in times of
drought. During the 50 years that biologists have tracked continental breeding
populations, we have witnessed three peaks in duck populations, and two
valleys. Each event coincided with times of wetland abundance or scarcity. Thus
far, the pattern has been remarkably cyclic (Figure 2). Valleys of about 23
million ducks, peaks of roughly 40 million, and an average breeding population
index of about 31 million birds. How can effective conservation programs be
implemented in such a dynamic environment? By taking the long view of prairie
conservation.
The long view acknowledges that duck populations will naturally build and
decline as an inevitable consequence of wet periods and drought. No human
intervention can change this reality. But because water and nesting cover are
the two critical elements that determine annual production, what we can do is
protect the wetland basins and the intact grasslands so that the table is set for
the ducks when Mother Nature provides the right conditions. As we protect this
baseline, we can also selectively implement wetland and grassland restorations
to compensate for the extensive habitat loss that has already occurred. Its a
dual-pronged approach that has served waterfowl conservationand Ducks
Unlimitedfor almost seven decades.
Where large tracts of intact habitat still exist, it makes sense to emphasize
the protection of these areas before they are lost.
Some detractors argue that securing the current base of habitat is not a
suitable stretch goal for conservation, and a few maintain that this approach
is flawed because it does not provide new, incremental ducks to the population.
But those who espouse these viewpoints overlook the current trends and the
pressures that exist in the PPR. The truth is, the prairies are under siege
like no time since the mid-1970s, when farmers were urged to plow fencerow to
fencerow. A duck that is never added to the fall flight because of the drainage
of a wetland or plowing of native grassland impacts population totals much the
same as not producing an additional duck using more intensive management
techniques. Moreover, in todays economy, guarding against the loss of habitat
is usually a far wiser business decision than only costly restoration of
habitat that is already degraded. For example, in much of the U.S. PPR, a
one-time payment of $45-110 per acre can secure a perpetual grassland easement
on the best waterfowl breeding habitat in the world. This is much more cost
effective when compared to more intensive management techniques that can be 10
times as expensive. The highest priority, therefore, should be to protect the
habitat base that provides for the duck population booms, like the one that
occurred in 1993-1999. If we dont secure the intact habitats before they
disappear, we will soon be in the unfortunate position of depending primarily
on intensive management and expensive restorations.
But protecting the base is a credible approach only if the threats are genuine
and losses are imminent. Are they? Lets examine the threats more closely.
President Bush recently announced that he continues to support no net loss of
wetlands, and that is positive. However, the U.S. Supreme Court decision that
removed isolated wetlands from protection under the Clean Water Act still
stands. This is arguably the gravest threat to the PPR and to North American
duck populations. The prairie potholes are the engines of the duck factory, and
no amount of secure grasslands or intensive management can make up for their
loss. Of additional concern is Canadas weaker wetland protection laws that
have allowed relatively greater rates of loss than south of the border.
Encouragingly, that trend is showing signs of reversing as Canadians embrace a
renewed interest in wetlands conservation. But now that U.S. laws have
effectively been weakened by the Courts interpretation, the only line of
defense that still protects prairie pothole wetlands in the United States is
the swampbuster provision of the Farm Bill. As with all such provisions,
swampbuster is up for review every time a new Farm Bill is crafted. The next
retooling is scheduled to begin in three or four years.
Second only to the wholesale loss of wetlands is the threat posed by the
ongoing destruction of native prairie, the backbone of North American duck
production. Big tracts of prairie are especially important, because duck
nesting success increases with the amount of grassland in the landscape.
Unfortunately, the much publicized mad cow disease (BSE, or bovine spongiform
encephalopathy) has halted a recent trend that was favoring cattle ranching
over cropping in parts of prairie Canada. In the blink of an eye, BSE now
threatens the economic viability of the Canadian beef industryand therefore
grasslandsacross much of prairie Canada.
In the United States, the conversion of native grassland to cropland has been
accelerating, pushed by world demand for grain, by favorable loan rates, and by
U.S. Department of Agriculture price supports. Of all the restorations
performed by Ducks Unlimited, bringing back native prairie is one of the most
challenging. Not only is it expensiveat least six times as expensive as an
easement purchased to protect prairie from being destroyed in the first
placebut it is also ecologically extremely difficult. When it comes to native
prairie, an ounce of prevention is indeed worth a pound of cure.
If native grasslands are the cake that feeds the duck booms, then Conservation
Reserve Program (CRP) lands are the frosting. Under CRP, landowners agree to
plant and maintain grassland on their marginal cropland for a 10-year period in
exchange for an annual government payment. The 4.7 million acres of CRP that
are currently enrolled in North and South Dakota provide nearly ideal nesting
cover. During 1992-1997, CRP contributed to a 30 percent improvement in duck
recruitment rates and added an additional 12.4 million birds to the fall
flight. But in 2007, 2.4 million acres of CRP contracts will expire in the
Dakotas alone. That represents 51 percent of all the remaining CRP in these
critical states. Another 1.4 million acres will come out of enrollment in
2008-2009. Acres coming out of the program today are not being replaced because
of new national ranking factors for CRP that favor areas outside of the PPR.
This change, coupled with attractive commodity price supports and upward trends
in world grain demand, makes it questionable whether even a fraction of the CRP
acreage will be re-enrolled. Fewer acres of CRP in the prairies will mean fewer
ducks in North America.
Even though these are big issues, the solutions are fairly obvious. Wetlands
can be secured through a combination of new laws and easements that compensate
landowners for protecting potholes. Similarly, disincentives can be provided
that help secure native grasslands, along with incentive-based approaches like
purchased grassland easements that benefit both ranchers and ducks. The ranking
systems for CRP can be changed again to reflect priorities that were present in
the 1985 Farm Bill, when millions of acres were first enrolled in the PPR.
These changes will take commitment and far-sighted leadership, but at least the
path is clear. Unfortunately, the potential solutions to other threats are more
elusive.
For example, scientists have discovered that prairie pothole wetlands are
growing old before their time. For decades, soil and wind erosion has deposited
about a quarter of an inch of sediment per year into the average prairie pothole.
Not surprisingly, the deposition is worse in wetlands surrounded by cropland,
as opposed to grassland. So whats the big deal about a quarter-inch of dirt?
For one, thats all it takes to severely depress aquatic invertebrates that
live a part of their life cycle in the mud of prairie wetlands. These
invertebrates are the food source for many ducks during the breeding season.
Moreover, since the average prairie pothole is only a few feet deep, a
deposition rate of a quarter-inch per year means a three-foot-deep wetland will
be filled completely in less than 150 years. Many prairie potholes have been
surrounded by cropland and therefore have been subject to sediment deposition
since the early 1900s.
Another unexpected source of concern for PPR ducks is biotech crops. New
varieties of soybeans and wheat are not only more drought tolerant, but many
also have an engineered resistance to nonselective herbicides. This makes them
capable of growing in sites that are now devoted to ranching. The problem is most
acute in central South Dakota, where biotech crops and world demand are fueling
the destruction of tens of thousands of acres of prime pintail breeding
habitat. Soybean fields dont grow pintails. Certainly, its a poignant
reminder that new technology has the potential to put all natural habitats at
risk. The conversion of native prairie could accelerate rapidly with the
introduction of biotech wheat, which seems destined to be widely adopted by
farmers. In the PPR, where wheat is king and farm profitability is front-page
news, vigorous debate has surfaced among farmers as to whether biotech crops
should be grown.
Conservation
and Society
Apart from the scientific arguments for and against the safety of biotech
crops, the debate over their use provides a valuable insight for waterfowl
conservationists. The lesson for waterfowl conservation is that science can
develop solutions, but society must embrace their application.
DU is a science-based organization. Science has honed our knowledge of
waterfowl biology; cutting-edge GIS computer software and LANDSAT satellite
imagery have helped us target the highest priority landscapes, and we have a
toolbox full of proven techniques. But these tools are implemented within a
society that has competing viewpoints on how wetlands, grasslands, and ducks
should figure into their future.
On both sides of the international border, those living in the PPR are facing
similar problems. There is an out-migration of people. Small towns are being
abandoned, and young people are leaving. Schools are being consolidated. The
traditional economic driver, agriculture, is moving rapidly to large operations
requiring relatively few people. It remains heavily dependent on government
subsidies. Understandably, these concerns generate apprehension about the
future, which promotes conservatism and a tendency to fall back on what has
worked in the past, namely an agro-economy that continues to pressure wetlands
and grasslands.
Biologists have a term for the maximum number of ducks that can be accommodated
in a given area. Its called the biological carrying capacity. In the PPR,
where economic and social concerns weigh heavily on peoples minds, the
political carrying capacity for conservation is the amount of habitat that
society feels should be set aside in fee-title ownership, conservation
easements, and protected wetlands. Unfortunately, there is often a large gap
between that political carrying capacity and the amount of secure habitat
needed to assure the long-term future of breeding ducks. In the minds of many
people, prairie wetlands and native grasslands are viewed as placeholders on
the landscape, waiting to be converted to a better, more profitable use.
Therein lies one of our biggest conservation challenges. The history of conservation
is that society tends not to place a high value on natural features until those
resources are almost gone. We cannot afford to repeat that lesson in the
prairies.
Conservation organizations need to promote the economic and quality-of-life
values of wetlands and grasslands, and DU is doing just that. In Canada, Ducks
Unlimited has taken the lead in promoting agricultural policy reform. DU is
actively working to ensure that policymakers recognize that establishment of
perennial cover on marginal croplands provides societal values beyond ducks and
other wildlife, including improved water quality, enhanced flood control, and
soil conservation. Since these ecological goods and services are being provided
by landowners, new agricultural policies should ensure that individuals who
conserve habitat are compensated accordingly. Adoption and eventual broadening
of such policies will be critical to our mission of restoring waterfowl habitat
in the Canadian PPR. Greencover Canada, an agricultural program that pays for
the conversion of cropland to perennial grassland, has recently been announced.
This is a very positive first step, and will improve habitat conditions on
acres that are enrolled, similar to the positive impacts of CRP in the United
States.
In the United States, wetland and grassland easements purchased from willing
landowners not only provide direct economic benefits, they also enable
individuals to achieve their vision for the future of their land. This is a
win-win situation that is popular with landowners and good for ducks. Likewise,
habitat restorations and management can provide not only improved waterfowl
habitat, but also economic returns in the form of hunting leases and
nature-based tourism, and can also enhance the quality of human life on the
land. In the new economy of the 21st century, where cyberspace shrinks the
world down to size, individuals and companies are choosing to locate in areas
that provide an enhanced quality of life. Landscapes that include open space,
wetlands, natural plant communities, and wildlife figure prominently in the
quality-of-life equation.
From
Insights to Action
The British biologist Thomas Henry Huxley had it right when he said, The great
end of life is not knowledge but action. Fortunately, in the PPR, opportunity
and knowledge have set the stage for action. Individuals and society are
awakening to the importance of prairie wetlands and grasslands. Today, hundreds
of ranchers are on waiting lists to sell conservation easements that will
permanently protect critical habitat, yet we lack funding and staffing to meet
the demand. Thousands of farmers would like to plant their existing cropland to
grass under the Greencover Canada and CRP programs. However, eligibility
criteria that select properties for CRP qualification are directing CRP away
from the PPR in the United States, and Green-cover in Canada suffers for lack
of funding. Much of society has come to recognize the value of wetlands for
clean water and flood control, yet isolated wetlands have fallen out of legal
protection under the U.S. Clean Water Act and have never received adequate
protection in Canada. Everybody wants a good quality of life, and natural
landscapes are a key element of that desire. Our challenge is translating this
knowledge to action.
Clearly, we must pick up the pace. Many landowners are reaching retirement age,
and when real estate changes hands, the new owners often consider alternative
uses for the land. We need to become more vocal advocates for sound public
policies that protect wetlands and grasslands, and we need to increase our
personal and financial commitments to prairie conservation. While individual
projects continue to be the building blocks of DUs work in the PPR, DUs
vision of the final product has expanded greatly over the years. We are
reaching for nothing less than securing for all time the waterfowl production
capacity of the Prairie Pothole Region. The challenges are daunting, but the
goal is achievable. Lets roll.
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Habitat Articles
Articles about current problems threatening waterfowl habitat
Hurricane Impacts on Wetlands and Waterfowl
As vital recovery work for people and their homes and businesses proceeds, biologists are assessing the impacts the storms had on Louisiana's coastal marshes...
America's Marsh
If North America is the land of plenty blessed with abundant natural resources, then Louisiana's coastal marsh is a strong candidate for capital.
Keepers of the Prairie
By the 1920s, it was thought that most of the tillable ground in Dakota Territory was already cropland. We then experienced the dust bowl years, with horrible impacts on farmers, ranchers, and the American psyche. Some of our prairie states were showing clear signs of widespread desertification. It has not abated.
DU Special Report: Prairies Under Siege: Part I - Ducks, Habitat Conservation, and Predators
A closer look at large-scale predator-control programs reveals that they are counterproductive to the long-term benefits of waterfowl and waterfowl hunters
DU Special Report: Prairies Under Siege: Part II - New Threats to Ducks & Waterfowling
North America's Prairie Pothole Region is facing the greatest potential loss of habitat in decades
DU Special Report: Prairies Under Siege: Part III - Science & Conservation
...Highlights how science underpins DU's choices about investing habitat dollars in a region crucial for waterfowl conservation and beset by new and continued threats to nesting habitat
DU Special Report: Prairies Under Siege: Part IV - The Future of the Prairies
Without aggressive measures to secure its habitat base, North America's duck factory faces an uncertain future

Keepers of the Prairie
By the 1920s, it was thought that most of the tillable ground in Dakota Territory was already cropland. We then experienced the dust bowl years, with horrible impacts on farmers, ranchers, and the American psyche. Some of our prairie states were showing clear signs of widespread desertification. It has not abated.
Rice and Ducks - Winter flooding of harvested rice fields is among the finest examples of waterfowl-friendly agriculture
Ducks and Winter Wheat - Making the Landscape Productive for Ducks and people
Benefits of Managing for Native Vegetation - When managing for waterfowl, native plant species should be considered whenever possible, especially in areas where a local agricultural base already exists. The real question you may ask is: Why?
Spring Habitat: The Neck of the Hourglass
- Spring staging habitats are vital stopover areas for migrating ducks and geese. These wetlands also strongly influence the birds' reproductive success on their breeding grounds
The Prairie Cycle: Droughts, Ducks, and Man
What have we learned? What do we do?

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